Laser eye surgery is performed using an excimer laser. This laser emits pulses of ultraviolet light, a special type of light energy invisible to the human eye. Each time a light pulse is emitted, a very subtle layer of cornea is removed, to slightly alter its curvature. Specialist medical software then allows the computer to determine the pattern of the pulses to remove the necessary corneal tissue.

There are two types of eye problems that can be corrected with eye laser: myopia (short sightedness), hypermetropia, commonly known as long sightedness, and astigmatism.

For short sightedness to be corrected, it’s necessary to decrease the curvature of the cornea so that it becomes flatter. The tissue of the cornea is then removed, following a disc-shaped pattern. For correcting long sightedness, the central portion of the cornea has to be remodelled by removing tissue in a doughnut-shaped pattern in order to make it steeper. Finally, for astigmatism to be corrected, it’s necessary to re-establish the symmetry of the cornea.